This invention relates to a pinion gear type rotating device, especially for use in electromagnetic interference characterization of a fiber optics transceiver, by which device a member such as a fiber optics transceiver can be held and rotated by at least 360 degrees about first, second and third axes extending across to each other. The invention further relates to a device for characterizing electromagnetic interference of a fiber optics transceiver and to methods for operating a pinion gear type rotating device according to the invention.
A fiber optics transceiver generates noise in a form of electromagnetic radiation when optical signal is transmitted through the transceiver. Electromagnetic interference (EMI) characterization is performed to detect level of such electromagnetic radiation from the transceiver from all possible directions.
EMI characterization is normally done inside an enclosed chamber. The transceiver is rotated 360 degrees in all directions by an engineer holding the said transceiver in his hands. The said method is highly inaccurate and tedious and a door of the chamber has to be left open for the hands to hold the transceiver, resulting to further inaccurate characterization results.
The door should be closed for EMI characterization of the fiber optics transceiver to be accurate. A turntable method is used where the fiber optics transceiver to be EMI characterized is placed on the turntable which rotates about a single axis. Although the EMI characterization can now be done with the door closed, the fiber optics transceiver is not able to be rotated in 360 degrees in all directions.
A belt driven manipulator is an improved version of both the hand method and turntable method described above. The said characterization can also be done with the chamber door closed and rotation of the fiber optics transceiver in all directions is achieved by rotating three wheels outside the chamber, which are connected to the belt driven manipulator in the chamber. However, slipping of the belt can occur during operation, resulting the fiber optics transceiver to be in an undefined position in the chamber. The characterization results hence become unreliable.